/Engine/Source/Runtime/Engine/Classes/GameFramework/GameUserSettings.h
Runs the hardware benchmark and populates ScalabilityQuality as well as the last benchmark results config members, but does not apply the settings it determines. Designed to be called in conjunction with ApplyHardwareBenchmarkResults
virtual void RunHardwareBenchmark ( int32 WorkScale, float CPUMultiplier, float GPUMultiplier )